Heat exchange apparatus



C. H. LEACH HEAT EXCHANGE APPARATUS Filed April 11, 1934 2 Sheets-Sheet l a as L w gl l 10 4 22 222 16 i u Z2 6'0 L 4 45 jlvenior 52 ,4 M

44 50 46 46 62 W W 66 11W Nov. 13, 1934. c. H. LEACH 1,980,627

EXCHANGE APPARATUS Filed A ril 11, 1954 2 Sheets-Sheet 2 Patented Nov. 13, 1934 UNITED STATES PATENT OFFICE The present invention relates to heat exchange apparatus, and more particularly to apparatus of this character designed for the condensation of hot oil vapor through the employment: of a liquid cooling medium which may be confined in its passagethrough the exchanger under a substantial pressure.

The purpose and object of thepresent invention is to insure that incipient leakage from heat exchangers of this type shall be confined for purpose of collection and excluded from contact with oxygen or air to avoid fire hazard in the event that the temperature of the cooling fluid should be above the combustion point if exposed to air.

With this general object in view, the features of the invention consist in certain novel features of construction, combinations and arrangements of parts hereinafter described and claimed, the advantages of which will be obvious to those skilled in the art from the following description. In the accompanying drawings illustrating the preferred form of the invention, Fig. 1 represents a section in elevation of a heat exchanger embodying the improved means for sealing in the pressure space, and Fig. 2 is a detail illustrating a slight modification of the structure shown in Fig. 1.

Referring particularly to the illustrated embodiment of the invention, the improvements are incorporated in a heat exchanger for condensing and fractionating oil vapor, of a design covered by a number of my prior patents and applications. This heat exchanger comprises, generally speakingfa tube support 10, which may be in the form of a casting or forging, generally circular in outline, and provided with an integral transverse tube sheet and partition 12, provided at its periphery with a circumferential flange having an upper portion 14 to provide and enclose one or more condensate basins, and a lower portion 16 to provide the outer enclosing wall for separated cooling liquid passages. The tube sheet has connected thereto and passing therethrough a series of cooling tubes 18, which extend in a generally vertical direction, and are provided with return headers in the shape of floating heads 20 at their opposite ends. Cooling liquid passes through the interior of the tubes from the liquid-passages 22 formed by the circumferential flange 16 and the intermediate partitions 24, the liquid being returned by the headers and caused to flow progressively through the tube series, as will be evident to those skilled in the art.

The vapor to be cooled is caused to pass exteriorly of the tubes in a confined space provided by an enclosing shell 26, having a domed closure 28 welded thereto at 30. The enclosing shell surmounts and is detachably connected at 32 to a nozzle ring and vapor annulus 34, provided with inlet and outlet nozzles 36 which direct the flow of incoming and outgoing vapor caused to flow in a circuitous path through the tube series by one or more intermediate partitions 38, all as will be evident to those skilled in the art. Condensate from the vapor rains downwardly along and between the tube series, and is collected within one or more basins at the upper side of the tube sheet 12.

The liquid passages 22 provided between the intermediate partitions 24 and by the circumferential flange 16 are closed by a detachable cover member 40, which is peripherally bolted to a flange 42 formed on the flange 16 by connecting bolts 44. The cover member is also intermediately bolted to enlarged and intermediate partition ribs 46 through, the bolting series 48. There may be one or more of these bolting series as'desired, and depending upon the pressure to be sustained.

The intermediate bolting ribs are formed integral with the tube sheet 12, and not only serve in and of themselves to resist distortion of the tube sheet under applied and unequally distributed pressures,

but also through the rigid intermediate bolting the rigid connection through the medium of the intermediate ribs 46. The cover member seals the liquid passages in conjunction with yielding gaskets 50 and 52, which are squeezed in position upon joining the cover to the bolting connections.

Although such a construction affordsa satisfactory medium for effectively sealing the liquid passages which in operation contain cooling-liquid under high pressure .and temperature, it may nevertheless be desirable to insure against any fire hazard in the event of incipient or accidental leakage from about the joint between the cover and connected parts. For this purpose I have found that by completelysealing the cover member joint and excluding air or oxygen therefrom, any leakage of high temperature liquid which would otherwise be combustible upon exposure to air is confined and may be directed away from the exchanger without damage. To this end, I propose as indicated in Fig. 1 to weld or otherwise seal a circumferential flange 60, about the exterior of the bolting flange 42, and connect to this flange the relatively light supplemental cover 62, preferably by bolts 64, which will suffice to seal the space around the joint and through the intermediate bolting connections where leakage may occur, and to collect and divert such leak- As indicated, the supplemental cover 62 may be provided with a centrally located outlet 66 for connection to a suitable drain. In addition, and

if so desired, I may conceivably fill the space within the supplemental cover with steam or other medium to exclude oxygen by the inlet shown in Fig. 2.

In the construction shown in Fig. 2, I have provided a similar supplemental cover 70 which, however, is bolted to a ring 72 welded into a circumferential recess 74 formed in the base member 10 so that the space enclosed by the supplemental cover not only seals the joint and intermediate bolting connections, but .also the peripheral bolting connections 44. Although the sealing of the peripheral bolting connections is not commensurate in its importance with the sealing of the joint and intermediate connections, nevertheless it may be desirable to provide this additional enclosure under certain circumstances,

It will be evident that with this construction the supplemental cover is not subjected to the pressure within the liquid passages, and that the pressure on the outer side of and below the heavy pressure member 40 is virtually at atmosphere and does not interfere or in any way militate against the pressure-holding characteristics of this member in its reinforcement of the tube sheet against distortion- As will be evident, the function of the supplementary cover member is to collect and confine leakage, if any, from about the joint formed by the cover member 40. By sealing the space about the joint in this manner, the cooling fluid may be excluded from the atmosphere, and the risk of fire hazard avoided if the temperature of the fluid is such as to normally ignite upon exposure to atmosphere. The supplementary cover under normalconditions of operation is inactive, andmerely'provides assurance that in' the event of sporadic leakage no damage will result.

What is claimed is:

1.- Heat exchange apparatus for handling hot oil vapor comprising a tubular cooling system,

.'means for providing flow of vapor about the tubular cooling system, passages for directing fluid flow through the interior of the cooling system, a cover member for detachably closing the fluid. passages designed to normallyresist the pressure therein, and a supplementary cover enclosing the pressure cover and surrounding the joint formed thereby. i V

2. Heat exchange apparatus comprising a tube support, a tubular cooling system connected to the support, cooling fluid passage formed at one side of the support communicating with the tubular cooling system, .a pressure cover detachably connected to the support and sealing the fluid passage, and a supplementary cover connected to the support about the pressure cover and surrounding the joint formed thereby.

3. Heat exchange apparatus comprising a tube support, a tubular cooling system connected to the support, a cooling fluid passage formed at one side of the support communicating with the tubular cooling system, a pressure cover. de-' tachably connected-to the support and sealing the fluid passage, and a-supplementary cover the supplementary cover having an outlet disposed age if it takes place, without contact with air. therein for the removal of leakage collected by the cover.

4, Heat exchange apparatus comprising a generally circular tube support, a tubular cooling system connected to the support, a shell supported from the support and surrounding the cooling system with provision for the entrance and exit of vapor, a liquid passage provided at the side of the support remote from the vapor space and in communication with the cooling system, a pressure cover connected to the support and designed to seal the liquid passage, and a comparatively light supplementary cover connected to the support surrounding the joint formed by the pressure cover for collecting and receiving leakage from the-pressure joint.

5. Heat exchange apparatus comprising a tube ing the fl'uid space, peripheral bolting connec-- tions between the flat cover member and support, a supplementary cover surrounding the pressure cover and the joint formed thereby, and means for connecting the supplementary cover to the support.

6. Heat exchange apparatus comprising a tube support, a tubular cooling system connected with the support, a fluid space in communication with the fluid system, a flat cover member for sealing the fluid space, peripheral bolting connections between the flat cover member and support, intermediate bolting connections between the cover member and support, a supplementary cover enclosing both series of bolting connections and the joints formed thereby, and means for connecting the supplementary cover to the support. 1

7. Heat exchange apparatus comprising a circular tube support member having a circumferential flange and intermediate ribs to provide cooling fluid passages, a tubular cooling system connected with the support and communicating with the passages, a flat circular cover connected to the support through the circumferential flange and intermediate ribs, a supplementary cover surrounding the pressure cover and the bolting connections, and means for connecting the supple mentary cover to the support. I

'8. Heat exchange apparatus comprising a tube support, a tubular cooling system connected therewith, a fluid space incommunication with the system, a pressure cover connected to the support for sealing the fluid space, a-supplementary cover surrounding the pressure cover and enclosing the joint formed thereby .to provide an enclosed space for the collection of leakage, and means for admitting non-combustible fluid such as steam or the like to the space enclosed by the-supplementary cover.

9. Heat exchange apparatus comprising a tube support having a circumferential flange and intermediate ribs to provide cooling fluid passages, a cover member connected to the circumferential flange and intermediate ribs by boltingconnections, a radial flange connected to the support and extending outwardly beyond the bolting connections, and a supplementaryv cover connected to the radial flange and enclosing the pressure cover and connections.

CHARLES H. LEACH.- 

